Steven Hayashi speaks to a reporter at the Contra Costa County Jail in Martinez, Calif. during an interview Friday, July 23, 2010. Hayashi, 52, owner of the five pit bulls, was arrested on suspicion of felony child endangerment and possession of mischievous animals that resulted in the death of his two year old step grandson Jacob Bisbee, who was mauled to death in their Concord home.(Dan Rosenstrauch/Staff)

Steven Hayashi enters the Bray Courthouse in Martinez, where he is on trial for the 2010 fatal dog mauling of his two-year-old grandson Jacob Bisbee, in Martinez, Calif., on Wednesday, Aug. 21, 2013. (Dan Rosenstrauch/Bay Area News Group)

MARTINEZ -- A Concord man faces up to 10 years in prison if convicted of involuntary manslaughter and child endangerment in the fatal mauling of his 2-year-old step-grandson by three pet pit bull dogs a prosecutor said the man knew to be vicious.

Steven Hayashi, 55, waived his right for his case to be heard by a jury, and Contra Costa Superior Court Judge John Kennedy will decide his guilt or innocence after a trial that began Wednesday and will continue on a sporadic schedule.

At issue is whether Hayashi should have foreseen the attack that killed toddler Jacob Bisbee and whether he is responsible for Jacob and his 4-year-old brother being unsupervised the July 22, 2010, morning Jacob wandered into an unlocked garage where the dogs were.

Prosecutor Mary Knox said the family's arrangement was that while Jacob's father, Michael Bisbee, was at work and his grandmother -- Hayashi's wife Leticia -- was sleeping off her night shift, Hayashi was responsible for taking care of the boys. Instead, that morning, he left the children alone so he could play tennis with his teenage son.

His five dogs were regularly separated into two packs, rotated between the garage and backyard. The garage door was left unlocked that morning, and there had been no efforts made to childproof the doorknob, Knox said.

The dogs had already killed two family pets and had been showing aggression toward Jacob. Knox said family members had been begging Hayashi to get rid of the dogs, warning him that something bad would happen.

Advertisement

"But as he told his wife, the dogs were his, and the children were his step-granchildren, and they should leave before the dogs," Knox told the judge in her opening statement.

Defense attorney David Cohen said that while Hayashi's actions show some negligence, it wasn't at the "gross negligence" standard that must be proven for a conviction.

Cohen said that when Hayashi left that morning he believed Bisbee was in his bedroom with Jacob and his brother.

Steven Hayashi speaks to a reporter at the Contra Costa County Jail in Martinez, Calif. during an interview Friday, July 23, 2010. Hayashi, 52, owner of the five pit bulls, was arrested on suspicion of felony child endangerment and possession of mischievous animals that resulted in the death of his two year old step grandson Jacob Bisbee, who was mauled to death in their Concord home.(Dan Rosenstrauch/Staff)

Cohen said the dogs had never bitten or attacked a person and, while Hayashi never let the children alone with the dogs, he didn't know them to be vicious animals.

Hayashi adopted the first dog, Sadie, from the Lake County animal shelter. She was supposed to have been spayed, but was in fact pregnant with a litter of five at the time of adoption, Hayashi said. They kept two of the puppies, Kiwi and Jake. Kiwi ended up impregnating Sadie, and another 11 puppies were born. Hayashi adopted out all but two, C.J. and Max.

"It's not easy to adopt out pit bull mixes," Cohen said. "Steven was afraid, and so was (his teen son) Christopher that if he returned to a shelter, they'd be euthanized," Cohen said.

Sadie, Kiwi and Jake killed Jacob, but all five dogs were euthanized after the attack that ripped the child apart and caused him to bleed to death.

The first witnesses Wednesday went over the crime scene photos of the small child's mangled body. Hayashi, sniffling, asked to take a break to compose himself.